MaskedEditExtender - Ajax Control Use in asp.net

<asp:TextBox ID="txt_DOB" runat="server"></asp:TextBox>

                                     

<cc1:CalendarExtender ID="txt_DOB_CalendarExtender" runat="server"                         Enabled="True" PopupButtonID="imgBtnCalender" TargetControlID="txt_DOB">                    </cc1:CalendarExtender>

                                     

<cc1:MaskedEditExtender ID="txt_DOB_MaskedEditExtender" runat="server"

AcceptNegative="Left" CultureAMPMPlaceholder=""                     CultureCurrencySymbolPlaceholder="" CultureDateFormat=""                        CultureDatePlaceholder="" CultureDecimalPlaceholder="" CultureName="en-US"

CultureThousandsPlaceholder="" CultureTimePlaceholder="" Enabled="True"

Mask="99/99/9999" MaskType="Date" TargetControlID="txt_DOB">

</cc1:MaskedEditExtender>

                   

<asp:ImageButton ID="imgBtnCalender" runat="server"

ImageUrl="~/Css/images/calendar-schedulehs.png" />

                  

<asp:RequiredFieldValidator ID="RequiredFieldValidator5" runat="server"

ControlToValidate="txt_DOB" ErrorMessage="Enter DOB" ValidationGroup="Reg"

Display="Dynamic" SetFocusOnError="True"></asp:RequiredFieldValidator>                   

                  

<asp:RangeValidator ID="Rv_NotGToday" runat="server"

ControlToValidate="txt_DOB" Display="None"                         ErrorMessage="Date Of Birth is not Greater than Today Date ..!" Type="Date"

ValidationGroup="Reg"></asp:RangeValidator> 

                       

<cc1:ValidatorCalloutExtender ID="Rv_NotGToday_ValidatorCalloutExtender"

runat="server" Enabled="True" TargetControlID="Rv_NotGToday">                    </cc1:ValidatorCalloutExtender>

protected void Page_Load(object sender, EventArgs e)

        {

TimeZoneInfo IND_ZONE = TimeZoneInfo.FindSystemTimeZoneById("India Standard Time");

Rv_NotGToday.MaximumValue = TimeZoneInfo.ConvertTimeFromUtc(DateTime.UtcNow, IND_ZONE).ToShortDateString();

Rv_NotGToday.MinimumValue = "12/1/1900";
}